Double Olympic champion Mo Farah has been questioned by the U.S. Anti-Doping Agency as part of an investigation into allegations surrounding his coach Alberto Salazar.

Double Olympic champion Mo Farah has been questioned by the U.S. Anti-Doping Agency as part of an investigation into allegations surrounding his coach Alberto Salazar.

The Sunday Mirror newspaper said Farah spoke with USADA in a hotel in London on Saturday for five hours. Britain’s Press Association said the meeting was believed to be routine and had been scheduled for some time.

Farah’s questioning came a day after he won the 3,000 meters in a Diamond League meeting at London’s Olympic Stadium.

The BBC aired allegations in June that Salazar, based in the United States, encouraged athletes to break doping rules. The 32-year-old Farah, the Olympic 5,000 and 10,000 gold medalist, was not implicated. Salazar has since published a detailed denial.